JP5460070B2 - Hydraulic elevator control device - Google Patents

Description

  The present invention relates to a control device for a hydraulic elevator that controls raising and lowering of a car by controlling the flow of pressure oil.

  For example, in a conventional hydraulic elevator as shown in Patent Document 1, a stop on-off valve is provided between a control on-off valve and a hydraulic jack in a hydraulic circuit. The stop valve is closed when the car is opened by a command from the control device, so that the ups and downs of the car due to the user getting on and off the car can be suppressed.

  In a conventional hydraulic elevator as shown in Patent Document 2, a hydraulic shut-off valve (hydraulic on-off valve: L10) is provided between a control on-off valve and a hydraulic jack in a hydraulic circuit. In this case, when the raising / lowering of the car is stopped, the solenoid of the hydraulic cutoff valve is demagnetized, the main valve (LV) of the hydraulic cutoff valve is closed, and the flow path of the pressure oil from the cylinder to the tank is blocked. As a result, similarly to the conventional hydraulic elevator as shown in Patent Document 1, the fluctuation of the ups and downs of the car due to the user getting on and off the car is suppressed.

  Specifically, in the conventional hydraulic elevator as shown in Patent Document 2, the flow path of the pressure oil from the control on / off valve side port to the jack side port in the hydraulic cutoff valve is when the solenoid is in a non-excited (demagnetized) state. It is formed. In addition, the flow path of the pressure oil from the jack side port to the control opening / closing valve side port in the hydraulic cutoff valve is formed when the solenoid is in an excited state.

  Therefore, the hydraulic shut-off valve is normally in a closed state (closed state), and is always in a state in which the amount of ups and downs of the car is small. For this reason, only when necessary (descent operation), the solenoid is excited to open the pressure oil flow path, and the door opening and closing is performed as in the conventional hydraulic elevator control device as shown in Patent Document 1. There is no need to excite the solenoid each time.

JP 11-322207 A JP 2008-44736 A

  Here, FIG. 4 is a block diagram showing a part of a conventional hydraulic elevator as shown in Patent Document 2. In FIG. In FIG. 4, a hydraulic shut-off valve L10 is provided in the hydraulic circuit between the hydraulic jack 1 for raising and lowering the car and the control on-off valve. The hydraulic shutoff valve L10 includes a first port A on the control opening / closing valve side, a second port B on the hydraulic jack 1 side, a main valve LV, a solenoid LE, and other adjustment mechanisms (LY, etc.).

  When the car is stopped, the solenoid LE is demagnetized. Thereby, the main valve LV is closed and the flow path of the pressure oil from the cylinder of the hydraulic jack 1 to the tank is shut off. Further, during the ascending operation, the hydraulic oil is driven by the hydraulic pump to pass through the port A, push down the main valve LV, and flow from the port B to the hydraulic jack 1. In this case also, it is not necessary to energize the solenoid LE.

  Further, during the descending operation, the solenoid LE is excited simultaneously with the opening command of the control on-off valve. As a result, a flow of port B → LE → port A occurs, and the main valve LV is opened. Then, the hydraulic oil flows out from the hydraulic jack 1 to the control on-off valve side, and the car descends. Further, after the car stop decision is made, as shown in FIG. 5, the solenoid LE is demagnetized simultaneously with the closing of the control on-off valve. That is, the control opening / closing valve and the hydraulic shutoff valve are closed simultaneously.

  Here, in the conventional hydraulic elevator as shown in FIG. 4, even if the hydraulic shut-off valve L10 is not fully closed for some reason, if the control on / off valve is fully closed, the car will reach a predetermined landing position. It can be stopped at the floor position. In this state, the effect of reducing the amount of ups and downs of the car is lost.

  On the other hand, in a conventional hydraulic elevator that does not use the hydraulic shut-off valve L10, if the control on-off valve is not fully closed, the car cannot stop at a predetermined landing position. The controller was able to detect that it occurred. That is, in a conventional hydraulic elevator that does not use the hydraulic shut-off valve L10, it is possible to detect an abnormality of the hydraulic equipment depending on whether or not the car can be stopped at a predetermined landing position.

  However, in the conventional hydraulic elevator as shown in FIG. 4, the car can be stopped at a predetermined landing position by providing the hydraulic shut-off valve L10 in the hydraulic circuit. For this reason, the control device cannot confirm that the control opening / closing valve is fully closed. Accordingly, in the conventional hydraulic elevator control device, the abnormality detection function for the hydraulic equipment has been reduced in conjunction with the provision of the hydraulic cutoff valve in the hydraulic circuit of the hydraulic elevator.

  The present invention has been made to solve the above-described problems, and in a hydraulic elevator in which a hydraulic shut-off valve is provided in a hydraulic circuit, a hydraulic elevator that can suppress a decrease in an abnormality detection function for hydraulic equipment. It aims at obtaining the control apparatus of.

  The hydraulic elevator control device according to the present invention includes a car, a hydraulic jack that drives the car up and down, a hydraulic pump that supplies pressure oil to the hydraulic jack, and a flow rate of pressure oil that is provided between the hydraulic pump and the hydraulic jack. A control on-off valve for performing control, and a hydraulic shut-off valve that is provided between the control on-off valve and the hydraulic jack and shuts off the flow of pressure oil between the control on-off valve and the hydraulic jack, and The hydraulic elevator is provided with a car position monitoring means for monitoring the position of the car. The position of the car is monitored via the car position monitoring means, and the control on-off valve and the hydraulic shut-off valve are opened and closed. The operation control unit controls the operation of the included car, and the operation control unit opens the control on / off valve when starting the descending operation of the car, and then opens the hydraulic shut-off valve and opens the control on / off valve. Oil after opening When the movement distance of the car to open the shut-off valve exceeds a predetermined value, it is to determine that an abnormality has occurred for the hydraulic pressure cut-off valve.

  According to the control apparatus for a hydraulic elevator according to the present invention, when the operation control unit starts the descending operation of the car, the control open / close valve is opened, the hydraulic shut-off valve is opened thereafter, and the control open / close valve is opened. When the travel distance of the car from when the hydraulic shut-off valve is opened exceeds a predetermined value, it is determined that an abnormality has occurred in the hydraulic shut-off valve. Therefore, in the hydraulic elevator provided with the hydraulic shut-off valve, The deterioration of the abnormality detection function for hydraulic equipment can be suppressed.

1 is a configuration diagram illustrating a hydraulic elevator according to Embodiment 1 of the present invention. FIG. It is a flowchart which shows the operation | movement at the time of the descent | fall start of the cage | basket by the control apparatus of FIG. It is a flowchart which shows the operation | movement at the time of the descent | fall start of the cage | basket by the control apparatus of FIG. It is a block diagram which shows the control apparatus of the conventional hydraulic elevator as shown to patent document 2. FIG. It is explanatory drawing for demonstrating the excitation timing of the solenoid of FIG. 4 by the control apparatus of the conventional hydraulic elevator.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
1 is a block diagram showing a hydraulic elevator according to Embodiment 1 of the present invention.
In FIG. 1, a hydraulic jack 1 and a car 2 supported by a plunger of the hydraulic jack 1 are provided in a hoistway of a building. The car 2 is raised and lowered in the hoistway by the vertical movement of the plunger of the hydraulic jack 1.

  A landing plate 3 is provided along the vertical direction at a position corresponding to the floor on the inner wall of the hoistway. A landing position detector 4 that can come into contact with the landing plate 3 is provided on the back surface or the side surface of the car 2. The landing position detector 4 generates an electrical signal by contacting the landing plate 3.

  Further, tension wheels 5A and 5B are respectively provided at the upper and lower portions of the hoistway, and the rope 6 is stretched endlessly between these tension wheels 5A and 5B. A part of the rope 6 is connected to the car 2. The tension wheels 5 </ b> A and 5 </ b> B rotate through the rope 6 as the car 2 moves up and down. A speed detector 7 is connected to the tension wheel 5B. The speed detector 7 generates an electrical signal corresponding to the rotational speed of the tension wheel 5B, that is, the ascending / descending speed of the car 2. The landing position detector 4 and the speed detector 7 constitute car position monitoring means.

  The hydraulic jack 1 is operated by pressure oil from a hydraulic power unit. The hydraulic power unit includes a hydraulic pump 11 that can rotate in the forward and reverse directions, a motor 12 for driving the hydraulic pump 11, a control on-off valve 13, a main circuit 14, a filter 15, an oil tank 16, a pilot circuit 17, and a first normally closed type. Solenoid valve 18, first variable throttle valve 19, second variable throttle valve 20, opening adjustment throttle mechanism 21, second normally closed solenoid valve 22, third variable throttle valve 23, and hydraulic shut-off valve (jack side opening / closing valve) 24 have.

  The hydraulic pump 11 and the motor 12 constitute a hydraulic pump device. The control on-off valve 13 has a valve body 13a, a main chamber 13b, and a back chamber 13c. The main chamber 13b and the back chamber 13c are partitioned by a valve body 13a. The main circuit 14 has first to third main pipes 14A to 14C. The first main pipe 14 </ b> A forms a pressure oil flow path between the hydraulic pump 11 and the main chamber 13 b of the control on-off valve 13. The second main pipe 14 </ b> B forms a pressure oil flow path between the main chamber 13 b of the control on-off valve 13 and the hydraulic cutoff valve 24. The third main pipe 14 </ b> C forms a pressure oil flow path between the hydraulic cutoff valve 24 and the cylinder of the hydraulic jack 1.

  The pilot circuit 17 includes a pressure oil inflow pipe 17A, a first pressure oil outflow pipe 17B, and a second pressure oil outflow pipe 17C. The pressure oil inflow pipe 17 </ b> A forms a flow path of pressure oil from the second main pipe 14 </ b> B to the back chamber 13 c of the control on-off valve 13. The first pressure oil outflow pipe 17 </ b> B forms a flow path of pressure oil from the back chamber 13 c of the control on-off valve 13 to the low pressure port that opens to the oil tank 16. The second pressure oil outflow pipe 17 </ b> C forms a flow path of pressure oil from the outlet of the opening adjustment throttle mechanism 21 to the low pressure port that opens to the oil tank 16.

  The first normally closed solenoid valve 18 and the second variable throttle valve 20 are provided in the first pressure oil outflow pipe 17B. The first variable throttle valve 19 is provided in the pressure oil inflow pipe 17A. The opening adjustment throttle mechanism 21 includes an adjustment screw 21a, a variable throttle 21b, and a sleeve 21c. The adjusting screw 21a and the sleeve 21c are for adjusting the opening area of the discharge port formed by the variable throttle 21b. The second normally closed solenoid valve 22 and the third variable throttle valve 23 are provided in the second pressure oil outflow pipe 17C.

  The hydraulic cutoff valve 24 has the same configuration as the hydraulic cutoff valve L10 shown in FIG. That is, the hydraulic shut-off valve 24 is provided between the control on-off valve 13 and the hydraulic jack 1 in the hydraulic circuit, and the flow of pressure oil between the control on-off valve 13 and the hydraulic jack 1 when closed. Shut off.

  The operation of the car 2 is controlled by a control device 100 as an operation control unit. The control device 100 monitors the position of the car 2 via the landing position detector 4 and the speed detector 7. Further, the control device 100 drives the hydraulic pump 11 and the motor 12, opens and closes the control opening / closing valve 13 (energization / deactivation of the first normally closed electromagnetic valve 18), and opens / closes the hydraulic cutoff valve 24 (opens the solenoid LE). (Demagnetization / excitation) are controlled to control the flow of pressure oil in the hydraulic elevator. Furthermore, the control device 100 controls the elevation of the car 2 by displacing the plunger of the hydraulic jack 1 by controlling the flow of pressure oil.

  In addition, when starting the ascending operation of the car 2, the control device 100 drives the hydraulic pump 11 in the forward direction and urges the first normally closed electromagnetic valve 18 to start the first pressure oil outflow pipe 17 </ b> B. open. The valve body 13a is pushed up from the main chamber 13b side to the back chamber 13c side by the pressure oil driven by the hydraulic pump 11, and the pressure oil in the back chamber 13c is discharged to the oil tank 16 through the first pressure oil outflow pipe 17B. Is done. As a result, the control on-off valve 13 is closed (fully closed).

  Thereafter, the pressure oil that has passed through the control on-off valve 13 flows to the hydraulic pressure cutoff valve 24, and the pressure oil pushes up the main valve LV of the hydraulic pressure cutoff valve 24. As a result, the hydraulic cutoff valve 24 is opened and pressure oil flows from the hydraulic cutoff valve 24 into the cylinder of the hydraulic jack 1. And the plunger is pushed up by the pressure oil, and the car 2 rises together with the plunger.

  Further, when stopping the ascending operation of the car 2, the control device 100 stops driving the hydraulic pump 11 and deactivates the first normally closed electromagnetic valve 18. As a result, the first normally closed solenoid valve 18 is closed, the flow path of the first pressure oil outflow pipe 17B is closed, and the control on-off valve 13 is closed. As a result, the flow of the pressure oil is stopped and the raising of the car 2 is stopped.

  On the other hand, when the control device 100 starts the downward operation of the car 2, first, the control device 100 excites the solenoid LE of the hydraulic cutoff valve 24. Along with this, the main valve LV of the hydraulic cutoff valve 24 is opened, and the hydraulic cutoff valve 24 is opened. Next, the control device 100 energizes the first normally closed solenoid valve 18 to open the flow path of the first pressure oil outflow pipe 17B. The pressure oil in the cylinder of the hydraulic jack 1 is pressurized by the weight of the car 2 and flows from the hydraulic shut-off valve 24 to the control on / off valve 13, and the valve body 13 a of the control on / off valve 13 is moved from the main chamber 13 b side to the back. Push up to the chamber 13c side.

  As a result, the control opening / closing valve 13 is opened, and the pressure oil in the cylinder of the hydraulic jack 1 is discharged to the oil tank 16 through the hydraulic cutoff valve 24, the control opening / closing valve 13, and the hydraulic pump 11. As a result, the plunger of the hydraulic jack 1 is displaced downward, and the car 2 is lowered with the displacement. At this time, the control device 100 controls the rotational speed in the regenerative drive of the hydraulic pump 11 and the motor 12 and controls the lowering speed of the car 2.

  Further, when stopping the descending operation of the car 2, the control device 100 first deenergizes the first normally closed electromagnetic valve 18 and closes the control opening / closing valve 13. Next, the control device 100 demagnetizes the solenoid LE and closes the hydraulic cutoff valve 24. Thereby, the flow of the pressure oil from the cylinder of the hydraulic jack 1 is stopped, and the lowering of the car 2 is stopped.

  Here, the control device 100 has an abnormality detection function for the control on-off valve 13 and the hydraulic shutoff valve 24 (hydraulic equipment). This abnormality detection function will be described. When the control device 100 starts the descent operation of the car 2, the car from when the control opening / closing valve 13 is opened to when the hydraulic shut-off valve 24 is opened after a predetermined time (for example, within about 1 second) elapses. 2, that is, the movement distance of the car 2 when only the hydraulic shutoff valve 24 is opened, is measured based on the electrical signals from the landing position detector 4 and the speed detector 7. Then, the control device 100 determines whether or not the measured movement distance of the car 2 exceeds a predetermined value.

  At this time, the control device 100 determines that the hydraulic shutoff valve 24 is normal when the moving distance of the car 2 is equal to or less than a predetermined value. On the other hand, the control device 100 determines that an abnormality has occurred in the hydraulic shut-off valve 24 when the moving distance of the car 2 exceeds a predetermined value. In addition, the control device 100 causes an abnormality in the hydraulic cutoff valve 24 when the descending distance of the car 2 from the landing reference position (position where the landing floor and the car floor are flush with each other) exceeds, for example, 15 mm. Judge. Thereafter, the control device 100 notifies the remote monitoring center (not shown) of the occurrence of an abnormality in the hydraulic cutoff valve 24 and stops the operation of the car 2.

  Further, when the control device 100 stops the downward operation of the car 2, a predetermined time (for example, within about 1 second) elapses after the control on-off valve 13 is closed until the hydraulic shut-off valve 24 is closed. The moving distance of the car 2, that is, the moving distance of the car 2 when only the control opening / closing valve 13 is closed, is measured based on the electrical signals from the landing position detector 4 and the speed detector 7. Then, the control device 100 determines whether or not the measured movement distance of the car 2 exceeds a predetermined value.

  At this time, the control device 100 determines that the control on-off valve 13 is normal when the moving distance of the car 2 is equal to or less than a predetermined value. In contrast, the control device 100 determines that an abnormality has occurred in the control on-off valve 13 when the moving distance of the car 2 exceeds a predetermined value. Note that the control device 100 determines that an abnormality has occurred in the control on-off valve 13 when the lowering distance of the car 2 from the landing reference position exceeds 15 mm, for example. Thereafter, the control device 100 notifies the remote monitoring center of the occurrence of an abnormality in the control on-off valve 13 and stops the operation of the car 2.

  Here, the control device 100 can be configured by a computer (not shown) having an arithmetic processing unit (CPU), a storage unit (ROM, RAM, hard disk, etc.) and a signal input / output unit. The storage unit of the computer of the control device 100 stores a program for realizing the operations shown in FIGS.

  Next, the operation at the start of the lowering of the car 2 by the control device 100 will be described. FIG. 2 is a flowchart showing the operation of the control device 100 of FIG. 1 when the car 2 starts to descend. In FIG. 2, first, the control device 100 checks whether or not a descent start condition for the car 2 (for example, a condition that is satisfied when the destination direction of the car 2 is set downward) is satisfied (step S11). At this time, if the control device 100 confirms that the descending activation condition for the car 2 is not satisfied, the control device 100 ends this operation as it is.

  At this time, when it is confirmed that the descending start condition for the car 2 is satisfied, the control device 100 opens the control on-off valve 13 (energizes the first normally closed electromagnetic valve 18), It waits for a time (for example, within about 1 second) (steps S12 and S13). And the control apparatus 100 measures the moving distance of the cage | basket | car 2 from the landing reference position when predetermined time passes (step S14), and confirms whether the measured moving distance is below a predetermined value. (Step S15).

  At this time, when the control device 100 confirms that the measured moving distance is equal to or less than the predetermined value, the control device 100 determines that the hydraulic cutoff valve 24 is normal and opens the hydraulic cutoff valve 24 (solenoid LE). Is excited: Step S16), the operation of the car 2 is continued as it is, and this operation is finished.

  On the other hand, when it is confirmed that the moving distance of the car 2 exceeds the predetermined value, the control device 100 determines that the hydraulic cutoff valve 24 is abnormal and notifies the remote monitoring center (step). S17). At the same time, the control device 100 opens the control on-off valve 13 (step S18), continues the operation of the car 2 as it is, and ends this operation. Here, the operation of the car 2 is continued because the car 2 can be moved up and down using only the control opening / closing valve 13 when an abnormality occurs only in the hydraulic shut-off valve 24.

  Next, the operation of the control device 100 when the car 2 is lowered will be described. FIG. 3 is a flowchart showing the operation of the control device 100 of FIG. In FIG. 3, first, the control device 100 checks whether or not a descent stop condition for the car 2 (for example, a condition that is established when the car 2 reaches the vicinity of the destination floor) is established (step S21). At this time, when the control device 100 confirms that the descending stop condition for the car 2 is not satisfied, this operation is finished as it is.

  At this time, when it is confirmed that the condition for stopping the descent of the car 2 is satisfied, the control device 100 closes the control opening / closing valve 13 (deenergizes the first normally closed electromagnetic valve 18), It waits for a time (for example, within about 1 second) (steps S22 and S23). And the control apparatus 100 measures the movement distance of the cage | basket | car 2 from the landing reference position when predetermined time passes (step S24), and confirms whether the measured movement distance is below a predetermined value. (Step S25).

  At this time, when the control device 100 confirms that the measured moving distance is equal to or less than the predetermined value, the control device 100 determines that the control on-off valve 13 is normal and closes the hydraulic shut-off valve 24 (solenoid LE). Is demagnetized: Step S26), the operation of the car 2 is continued as it is, and this operation is finished.

  On the other hand, when it is confirmed that the moving distance of the car 2 exceeds the predetermined value, the control device 100 closes the hydraulic shutoff valve 24 (step S27), and the control on / off valve 13 is abnormal. It is determined that there is, and the remote monitoring center is notified (step S28). Further, the control device 100 stops the operation of the car 2 (step S29), and ends this operation.

  According to the control apparatus for a hydraulic elevator as described above, the control apparatus 100 opens the control on-off valve 13 and then opens the hydraulic shut-off valve 24 when starting the descending operation of the car 2. Then, the control device 100 determines that an abnormality has occurred in the hydraulic cutoff valve 24 when the moving distance of the car 2 from the opening of the control opening / closing valve 13 to the opening of the hydraulic cutoff valve 24 exceeds a predetermined value. To do. With this configuration, in the hydraulic elevator in which the hydraulic cutoff valve 24 is provided in the hydraulic circuit, the abnormality of the hydraulic cutoff valve 24 can be detected, and the deterioration of the abnormality detection function for the hydraulic equipment can be suppressed.

  Further, the control device 100 closes the control on-off valve 13 and then closes the hydraulic shut-off valve 24 when stopping the descending operation of the car 2. Then, the control device 100 determines that an abnormality has occurred in the control on-off valve 13 when the moving distance of the car 2 from when the control on-off valve 13 is closed to when the hydraulic shut-off valve 24 is closed exceeds a predetermined value. To do. With this configuration, in the hydraulic elevator in which the hydraulic cutoff valve 24 is provided in the hydraulic circuit, the abnormality of the control on-off valve 13 can be detected, and the deterioration of the abnormality detection function for the hydraulic equipment can be suppressed.

  In the first embodiment, the control device 100 continues the operation of the car 2 after step S18 shown in FIG. However, the present invention is not limited to this example, and the control device 100 may stop the operation of the car 2 when it is determined that the hydraulic cutoff valve 24 is abnormal.

  In the first embodiment, the control device 100 performs the abnormality detection operation shown in FIGS. 2 and 3 during normal operation of the elevator. However, the present invention is not limited to this example. For example, the control device 100 may perform the abnormality detection operation shown in FIGS. 2 and 3 at the time of maintenance inspection or the first operation after the elevator is turned on.

  Further, in the first embodiment, both the landing position detector 4 and the speed detector 7 are used as car position monitoring means. However, the present invention is not limited to this example, and only one of the landing position detector 4 and the speed detector 7 may be used as the car position monitoring means.

  In the first embodiment, the hydraulic cutoff valve 24 is incorporated in the hydraulic power unit (in the casing). However, the present invention is not limited to this example, and the hydraulic cutoff valve 24 may be disposed in the vicinity of the hydraulic jack 1 independently of the hydraulic power unit.

  DESCRIPTION OF SYMBOLS 1 Hydraulic jack, 4 Landing position detector, 5 Control on-off valve, 7 Speed detector, 11 Hydraulic pump, 12 Motor, 13 Control on-off valve, 24 Hydraulic shut-off valve, 100 Control device.

Claims (2)

A car, a hydraulic jack for raising and lowering the car, a hydraulic pump for supplying pressure oil to the hydraulic jack, and a control opening and closing for controlling the flow rate of pressure oil provided between the hydraulic pump and the hydraulic jack A hydraulic shut-off valve that shuts off a flow of pressure oil between the control on-off valve and the hydraulic jack by being provided and closed between the valve, the control on-off valve, and the hydraulic jack; and A hydraulic elevator control device provided in a hydraulic elevator provided with a car position monitoring means for monitoring a position,
An operation control unit that monitors the position of the car via the car position monitoring means and controls the operation of the car including opening and closing of the control on-off valve and the hydraulic shut-off valve;
The operation control unit opens the control on-off valve when starting the descending operation of the car, then opens the hydraulic shut-off valve, opens the control on-off valve, and then opens the hydraulic shut-off valve. The hydraulic elevator control device, wherein when the moving distance of the car until opening exceeds a predetermined value, it is determined that an abnormality has occurred in the hydraulic shut-off valve. A car, a hydraulic jack for raising and lowering the car, a hydraulic pump for supplying pressure oil to the hydraulic jack, and a control opening and closing for controlling the flow rate of pressure oil provided between the hydraulic pump and the hydraulic jack A hydraulic shut-off valve that shuts off a flow of pressure oil between the control on-off valve and the hydraulic jack by being provided and closed between the valve, the control on-off valve, and the hydraulic jack; and A hydraulic elevator control device provided in a hydraulic elevator provided with a car position monitoring means for monitoring a position,
An operation control unit that monitors the position of the car via the car position monitoring means and controls the operation of the car including opening and closing of the control on-off valve and the hydraulic shut-off valve;
The operation control unit closes the control open / close valve when stopping the descending operation of the car, then closes the hydraulic shut-off valve, closes the control open / close valve, and then closes the hydraulic shut-off valve. A control apparatus for a hydraulic elevator, wherein when the moving distance of the car until closing exceeds a predetermined value, it is determined that an abnormality has occurred in the control on-off valve.

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